INFO: task systemd-shutdow:1 blocked for more than 143 seconds. Not tainted 5.11.0-rc7-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:systemd-shutdow state:D stack:22904 pid: 1 ppid: 0 flags:0x00000000 Call Trace: context_switch kernel/sched/core.c:4327 [inline] __schedule+0x91b/0x1f90 kernel/sched/core.c:5078 schedule+0xcb/0x270 kernel/sched/core.c:5157 wait_for_device_probe+0x1be/0x220 drivers/base/dd.c:704 device_shutdown+0x18/0x5c0 drivers/base/core.c:4180 kernel_restart_prepare kernel/reboot.c:76 [inline] kernel_restart+0x61/0xa0 kernel/reboot.c:246 __do_sys_reboot+0x31e/0x3e0 kernel/reboot.c:349 do_syscall_64+0x2d/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f80895388c6 RSP: 002b:00007ffd77f8cac8 EFLAGS: 00000202 ORIG_RAX: 00000000000000a9 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f80895388c6 RDX: 0000000001234567 RSI: 0000000028121969 RDI: fffffffffee1dead RBP: 00007ffd77f8cb58 R08: 0000000000002800 R09: 0000000000000005 R10: 0000000000000002 R11: 0000000000000202 R12: 0000000000000000 R13: 0000000000000000 R14: 00005567edf6c150 R15: 00007ffd77f8ce48 Showing all locks held in the system: 1 lock held by systemd-shutdow/1: #0: ffffffff87952f08 (system_transition_mutex){+.+.}-{3:3}, at: __do_sys_reboot+0x1a3/0x3e0 kernel/reboot.c:346 1 lock held by khungtaskd/1270: #0: ffffffff87a784a0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x269 kernel/locking/lockdep.c:6259 5 locks held by kworker/0:9/10932: #0: ffff888103f9f138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888103f9f138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff888103f9f138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff888103f9f138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff888103f9f138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff888103f9f138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x871/0x1580 kernel/workqueue.c:2246 #1: ffffc90001dffda8 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8a5/0x1580 kernel/workqueue.c:2250 #2: ffff8881092c0218 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:737 [inline] #2: ffff8881092c0218 (&dev->mutex){....}-{3:3}, at: hub_event+0x1c1/0x4320 drivers/usb/core/hub.c:5537 #3: ffff88810ca98218 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:737 [inline] #3: ffff88810ca98218 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7a/0x4a0 drivers/base/dd.c:889 #4: ffff888107c1f1a8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:737 [inline] #4: ffff888107c1f1a8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7a/0x4a0 drivers/base/dd.c:889 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1270 Comm: khungtaskd Not tainted 5.11.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x107/0x163 lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x46/0xe0 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1da/0x200 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline] watchdog+0xd32/0xf70 kernel/hung_task.c:294 kthread+0x38c/0x460 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.11.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:task_stack_page include/linux/sched/task_stack.h:21 [inline] RIP: 0010:in_task_stack+0x0/0x40 arch/x86/kernel/dumpstack.c:35 Code: 41 5d e9 63 00 00 00 4c 89 ee 48 c7 c7 c0 3f 8b 87 e8 84 b6 59 fc e9 60 ff ff ff cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc <48> 8b 46 20 48 8d 88 00 80 00 00 48 39 f8 77 21 48 39 f9 76 1c 48 RSP: 0018:ffffc90000007688 EFLAGS: 00000082 RAX: dffffc0000000000 RBX: ffffffff878520c0 RCX: ffffc90000007750 RDX: ffffc90000007730 RSI: ffffffff878520c0 RDI: ffffc900000076e0 RBP: ffffc90000007730 R08: 0000000000000001 R09: ffffc90000007730 R10: fffff52000000ef1 R11: 000000000000003f R12: ffffc900000076e0 R13: ffffc90000007730 R14: ffffc90000007768 R15: ffffc90000007730 FS: 0000000000000000(0000) GS:ffff8881f6800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffd77f8bff8 CR3: 0000000104096000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: get_stack_info_noinstr+0x14/0x110 arch/x86/kernel/dumpstack_64.c:157 get_stack_info+0x2d/0x90 arch/x86/kernel/dumpstack_64.c:183 __unwind_start+0x4ae/0x800 arch/x86/kernel/unwind_orc.c:665 unwind_start arch/x86/include/asm/unwind.h:60 [inline] arch_stack_walk+0x5c/0xe0 arch/x86/kernel/stacktrace.c:24 stack_trace_save+0x8c/0xc0 kernel/stacktrace.c:121 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track+0x1c/0x30 mm/kasan/common.c:46 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:356 ____kasan_slab_free+0xe1/0x110 mm/kasan/common.c:362 kasan_slab_free include/linux/kasan.h:192 [inline] slab_free_hook mm/slub.c:1547 [inline] slab_free_freelist_hook+0x5d/0x150 mm/slub.c:1580 slab_free mm/slub.c:3143 [inline] kfree+0xdb/0x390 mm/slub.c:4125 dummy_timer+0x1adc/0x32a0 drivers/usb/gadget/udc/dummy_hcd.c:1965 call_timer_fn+0x1a5/0x630 kernel/time/timer.c:1417 expire_timers kernel/time/timer.c:1462 [inline] __run_timers.part.0+0x67c/0xa10 kernel/time/timer.c:1731 __run_timers kernel/time/timer.c:1712 [inline] run_timer_softirq+0x80/0x120 kernel/time/timer.c:1744 __do_softirq+0x1b0/0x944 kernel/softirq.c:343 asm_call_irq_on_stack+0xf/0x20 __run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline] do_softirq_own_stack+0x80/0xa0 arch/x86/kernel/irq_64.c:77 invoke_softirq kernel/softirq.c:226 [inline] __irq_exit_rcu kernel/softirq.c:420 [inline] irq_exit_rcu+0x110/0x1a0 kernel/softirq.c:432 sysvec_apic_timer_interrupt+0x43/0xa0 arch/x86/kernel/apic/apic.c:1100 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:629 RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:29 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:79 [inline] RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:169 [inline] RIP: 0010:acpi_safe_halt drivers/acpi/processor_idle.c:111 [inline] RIP: 0010:acpi_idle_do_entry+0x1c9/0x250 drivers/acpi/processor_idle.c:516 Code: 1d bd 93 fb 84 db 75 ac e8 94 b6 93 fb e8 df 70 99 fb e9 0c 00 00 00 e8 85 b6 93 fb 0f 00 2d 3e 27 7c 00 e8 79 b6 93 fb fb f4 <9c> 5b 81 e3 00 02 00 00 fa 31 ff 48 89 de e8 54 be 93 fb 48 85 db RSP: 0018:ffffffff87807d60 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffffffff878520c0 RSI: ffffffff85abe707 RDI: ffffffff85abe6f1 RBP: ffff888103a59064 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff81455808 R11: 0000000000000000 R12: 0000000000000001 R13: ffff888103a59000 R14: ffff888103a59064 R15: ffff88810598f804 acpi_idle_enter+0x355/0x4f0 drivers/acpi/processor_idle.c:647 cpuidle_enter_state+0x1b1/0xc80 drivers/cpuidle/cpuidle.c:237 cpuidle_enter+0x4a/0xa0 drivers/cpuidle/cpuidle.c:351 call_cpuidle kernel/sched/idle.c:158 [inline] cpuidle_idle_call kernel/sched/idle.c:239 [inline] do_idle+0x3d5/0x580 kernel/sched/idle.c:299 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:396 start_kernel+0x46d/0x48e init/main.c:1061 secondary_startup_64_no_verify+0xb0/0xbb